【摘要】：磁化率隨著溫度的變化特征測(cè)量(κ-T曲線)可以用來(lái)確定磁性礦物類型及加熱過(guò)程中的礦相變化。前人對(duì)松遼盆地松科1井南孔白堊系嫩江組一段上部至二段下部(972.46-1060.24m)的30個(gè)代表性樣品進(jìn)行了κ-T曲線測(cè)量,發(fā)現(xiàn)樣品的磁化率值主要受控于順磁性礦物,絕大部分樣品的冷卻曲線明顯高于加熱曲線,說(shuō)明加熱過(guò)程中有新的強(qiáng)磁性礦物生成,其居里溫度在~500-560℃之間(李海燕等,2017)。但是,前人的研究未能確定新生成磁性礦物的類型,也未能確定該強(qiáng)磁性礦物來(lái)源于哪種礦物的轉(zhuǎn)變,僅推測(cè)可能來(lái)自粘土礦物的高溫段轉(zhuǎn)化�；诖�,本論文選擇純的粘土礦物、長(zhǎng)石單晶和嫩江組樣品開(kāi)展了新的研究,以期揭示嫩江組黑色泥巖樣品加熱后磁性增強(qiáng)的機(jī)制。本論文對(duì)純的粘土礦物、長(zhǎng)石單晶和松科1井南孔代表性樣品進(jìn)行了磁化率隨溫度變化特征的測(cè)量(高、低溫κ-T曲線)、粉晶X射線衍射實(shí)驗(yàn)(XRD)、掃描電鏡觀察(SEM)和能譜分析(EDS),取得了以下成果:1.純的粘土礦物中,綠泥石和伊蒙混層樣品的熱穩(wěn)定性較弱,加熱后有新的強(qiáng)磁性礦物生成,磁化率值增大。其中,含菱鐵礦的綠泥石樣品因菱鐵礦晶體中有Mg~(2+)和Mn~(2+)等離子,加熱后生成錳鉻鐵礦,其居里溫度為~520℃。蒙脫石和高嶺石樣品的熱穩(wěn)定性強(qiáng),其κ-T曲線的加熱曲線和冷卻曲線基本可逆,未見(jiàn)明顯的礦相轉(zhuǎn)變。2.純的長(zhǎng)石單晶顆粒的熱穩(wěn)定性強(qiáng),其κ-T曲線的加熱曲線和冷卻曲線基本可逆,未見(jiàn)明顯的礦相轉(zhuǎn)變。但綠泥石化長(zhǎng)石單晶顆粒和弱風(fēng)化的鉀長(zhǎng)石單晶顆粒的熱穩(wěn)定性較弱,加熱后有少量磁鐵礦生成,磁化率值增大。3.在氬氣環(huán)境下的加熱過(guò)程中,當(dāng)加熱溫度高于~350℃時(shí),嫩江組黑色泥巖樣品的磁性增強(qiáng)。該磁性增強(qiáng)來(lái)源于樣品在加熱過(guò)程中發(fā)生的礦相轉(zhuǎn)變,推測(cè)其過(guò)程為:在石英的參與下,伊利石、高嶺石等粘土礦物與含鐵、鎂的礦物反應(yīng),轉(zhuǎn)變?yōu)樵颇�、微量磁鐵礦和較多的含Mg/Mn的磁鐵礦。其中,含Mg/Mn的磁鐵礦的居里溫度為~520℃。4.在氬氣環(huán)境下的加熱過(guò)程中,嫩江組黑色泥巖樣品中的黃鐵礦在熱處理過(guò)程中轉(zhuǎn)變?yōu)榉磋F磁性的六方磁黃鐵礦,對(duì)其加熱過(guò)程中的磁性增強(qiáng)沒(méi)有明顯影響。
[Abstract]:The characteristic measurement of magnetic susceptibility with temperature (魏 -T curve) can be used to determine the type of magnetic minerals and the change of mineral phases during heating. Thirty representative samples (972.46-1060.24m) from the upper part to the lower part (972.46-1060.24m) of the first member of the Cretaceous Nenjiang formation in the south hole of Songke-1 well in Songliao Basin were measured. It was found that the magnetic susceptibility of the samples was mainly controlled by paramagnetic minerals. The cooling curves of most of the samples were obviously higher than those of the heating curves, indicating that new strong magnetic minerals were formed during heating, and their Curie temperature ranged from 500 鈩，

本文編號(hào)：2218392